Airport communication systems comprise a large number of terminals which are shared between a variety of airlines, each having their own departure control system (DCS). A departure control system is a server containing details relating to the departures for the airline (passenger records, flight details etc.). As the terminals are shared between airlines (for instance, at departure gates or check-in desks), each terminal must be able to communicate effectively with a variety of departure control systems. To this end, virtualization has been implemented such that the terminals themselves are clients of a virtualization server which runs virtual applications for the clients. This allows users working for different airlines to share the same terminal and, using the terminal as a basis, interact effectively with their airline's DCS (checking passengers in, accessing flight information, etc.).
The nature of airports is such that there are a large number of peripheral devices, many of which are not in common use outside of the airport environment (for example, baggage tag printers or boarding pass bar code scanners). These peripherals need to communicate with the terminals as well as the external servers to enable their operation based on up to date information as provided by the relevant departure control system.
Each terminal has a peripheral manager which contains drivers for peripherals connected to it and which establishes communication between the terminal and the peripherals. These peripheral managers are limited in their ability to communicate with server based (virtual) applications due to the use of non-static IP addresses and the need for IP address translation when communicating across networks comprising a mix of public and private addressing schemes.
One means of implementing communication between peripheral devices and various departure control systems is to direct communication based on fixed IP addresses and hostnames. This solution is problematic given the limited availability of public IP addresses and also present issues relating to security, firewalls and mobile data modes where 3G and/or 4G networks are used. Further problems arise from the need for many routing configurations that must be established and effectively managed, and the need to manage multiple stakeholders providing different elements of the communications, for example, airport authorities, network providers, airport information providers etc.
In addition, firewalls often block communication channels which are established by external devices, unless specific rules allowing communication from said devices have been established. This means that communication from an external virtualization server to peripherals within a local area network may well be blocked. To set up rules for each and every peripheral would be a complex and time consuming process for large networks, such as those implemented in airports.
Many virtualization protocols, however, do not allow external applications to establish and use virtual channels within the communication link between the virtualization server and the client.
Accordingly, there is a need for a flexible means of establishing communication between an application virtualized on an external server and a peripheral locally connected to a client.